1. Field of Invention
The invention relates to an optical apparatus. More particularly, the invention relates to a projection apparatus.
2. Description of Related Art
A projection apparatus is an apparatus used to produce an image with large size. The imaging mechanism of the projection apparatus is that an illuminating beam generated by a light source is transformed into an image beam by a light valve and then the image beam is further transformed into a projecting beam by a projection lens, so as to project the projecting beam onto a screen or a wall to form an image. Due to the development of projecting technology and reducing the fabrication cost, the application of projection apparatus has extended from the use in business to the use in home.
For a conventional projection apparatus, the appearance of the conventional projection apparatus usually is a flat shape, so the circuit boards inside the conventional projection apparatus are usually divided into two circuit boards. One circuit board includes a digital micro or device (DMD) chip and a control module of the DMD chip. Another circuit board includes the central processing unit (CPU) of the projection apparatus. In addition, the signals between the two circuit boards are transmitted by an one-to-one connector or a flat cable. However, the above assembling manner may cause an abnormal image or an abnormal operation of the host, due to the factors of poor quality for the connector or the flat cable, poor assembly tolerance, and improper assembly. U.S. Pat. Nos. 6,155,687, 7,301,691, and 7,883,215 have disclosed an projection apparatus, of which the DMD chip is directly implemented on the motherboard to reduce abnormal effect due to the above factors of poor quality for the connector or the flat cable, poor assembly tolerance, and improper assembly.
Further, the electrical connector of the projection apparatus for communicating with an external device is usually implemented on the edge region of the motherboard and the port of the connector is exposed to an opening of the apparatus casing. As a result, the projection apparatus can receive the electronic signals from outside, such as the video signals, to correspondingly produce the image. However, when the appearance of the apparatus casing has been changed, the location of the connector on the motherboard has to be adjusted as well. This would cause re-design for the motherboard. The cost would increase. The U.S. Patent Publication 2010/0073581 also discloses a projector, which uses an expansion module by external attachment to receive the video signal.